1. Field of the Invention
The present invention, in general relates to woodworking and, more particularly, to devices used to form a box joint or a corner joint.
In woodworking, it is often necessary to securely join two pieces of wood together at a right angle. This occurs at corners when two pieces of wood merge together. A common example is when constructing boxes. A corner connection of two pieces of wood is sometimes also referred to as a “joint” or as a “corner joint”.
It is well known in woodworking, that the strongest right angle joint (i.e., corner joint) possible is called a box joint. A box joint consists of a plurality of cut out segments, each called a dado, formed in each piece at each end. They must be cut so that the two pieces of wood match perfectly at the corner, with even tops and bottoms. Each of the cuts must be the same size as the fingers in the opposite piece. Furthermore, the spacing between each is critical. Once formed, the corners are fitted and glued together, each finger being inserted and glued into each corresponding dado cut.
Ideally, a small excess amount of material is provided for sanding. Accordingly, the dado cuts extend into the wood an amount that slightly exceeds the thickness of the wood, which results in a slight protrusion of each set of fingers extending out in each direction at the corner.
A corner joint that includes such a plurality of fingers and dado cuts that cooperate with each other is called a “box joint”. It is also sometimes referred to as a “finger joint”. Although box joints are the strongest corner joint possible and are attractive (i.e., a box joint's very appearance exudes quality of construction), they are seldom used, except in the most expensive pieces of furniture.
The reason for this lack of use is because they are especially difficult to make. They take a lot of time and labor, for example, there is much careful measurement required to ensure accuracy and to avoid error. An error in just one of many cuts will ruin the piece of wood, which may have already had a lot of work expended in its preparation.
Not only does each piece of wood that is to be joined require careful measurement as to where the dado cuts will be made, they must match perfectly with the fingers of the corresponding piece of wood. In other words the fingers of a first piece of wood must correspond with the dado cuts of the second piece of wood that is used to form the corner joint.
Prior art devices generally produce unsatisfactory results. They provide a reference that applies an expansive force at the bottom of the fingers, which tends to separate the fingers and introduce error. There is little or no indication of where to make each successive cut in the first piece of wood and there is no indication for making the cuts in the next piece of wood that will correspond perfectly with the cuts that have been made in the current (first) piece. For the homeowner or small scale woodworker, making box joints presents a formidable challenge.
For the woodworking novice, just learning these techniques, the challenge is substantial. Many people abandon their desire to progress in the woodworking arts because of an inability that they experience in making a successful box joint.
Accordingly, there exists today a need for a box joint fixture and method for cutting box joints to form a corner joint.
Clearly, such an apparatus would be a useful and desirable device and such a method would be similarly well received.
2. Description of Prior Art
Box joint fixtures are, in general, known. For example, the following patents describe a type of this device:
U.S. Pat. No. 6,041,837 to Hansen, Mar. 28, 2000.
While the structural arrangements of the above described device, at first appearance, may have certain similarities with the present invention, it differs in material respects. These differences, which will be described in more detail hereinafter, are essential for the effective use of the invention and which admit of the advantages that are not available with the prior devices.